360{20 {0 Reflex reflector

ABSTRACT

A reflex reflector which when vertically oriented spatially is adapted to continuously retro-reflect incident light rays horizontally striking such anywhere within an included angle of about 360*. Such reflector uses four reflective surfaces, arranged into two pairs of two surfaces each, the surfaces of each pair being in opposed, parallel relationship to each other, the pairs being oriented at 90* relative to each other. Each surface has reflex reflector facets adapted to retro-reflect over an angle of + OR - 45*.

United States Patent [191 Nagel 360 REFLEX REFLECTOR Robert I. Nagel,Skokie, lll.

Assignee: Beatrice Foods Co., Elgin, 111.

Filed: Dec. 28, 1973 Appl. No.: 429,098

Inventor:

[52] US. Cl. 350/103; 350/97; 404/9;

' 1 16/63 Int. Cl. G02B 5/12 Field of Search 350/97-109;

References Cited UNITED STATES PATENTS 1,813,874 7/1931 Eskils on350/102 3,541,606 11/1970 Heenan 350/103 [111 3,905,680 [4 1 Sept. 16,1975 2/1973 Kannenberg 350/97 9/1974 Brady 116/63 P PrimaryExaminer-Alfred E. Smith Assistant ExaminerMichael J. Tokar [57]ABSTRACT A reflex reflector which when vertically oriented spatially isadapted to continuously retro-reflect incident light rays horizontallystriking such anywhere within an included angle of about 360. Suchreflector uses four reflective surfaces, arranged into two pairs of twosurfaces each, the surfaces of each pair being in opposed, parallelrelationship to each other, the pairs being oriented at 90 relative toeach other. Each surface has reflex reflector facets adapted toretro-reflect over an angle of i 45.

11 Claims, 17 Drawing Figures 360 REFLEX REFLECTOR BACKGROUND OF THEINVENTION In many applications for reflex reflectors, there is a needfor horizontal 360 viewability such as, for example, on bicycles, onconstruction sites, on airport runways, on entrances to side lanes, andthe like. Because of their inherent retro-reflective properties, it isnecessary to employ a plurality of prior art standard reflex reflectorsof the molded plastic type with flat faces in order to achieve full 360viewability since individual such reflectors with flat faces arecharacteristically viewable over angles of only about 30 horizontallymeasured on either side of the face thereof. There is thus a strong andlong felt need in the art for a simple, economical, reflex reflectorconstruction employing molded plastic (e.g. acrylic resin,polycarbonate, or the like) which can provide 360 viewabilityhorizontally.

BRIEF SUMMARY OF THE INVENTION The present invention is directed toreflex reflector bodies adapted to retro-reflect incident light anywherewithin an included angle of about 360, measured in one plane. Such abody characteristically has four retro-reflective, generally planarsurface portions. These portions are arranged into two pairs of twoportions each. Each portion of each pair is generally in opposed,parallel relationship to the other thereof. One such pair is normallydisposed relative to the other thereof. Support means hold each pair infixed, substantially nonoverlapping adjacent relationship to the otherthereof. The interrelationship between said portions is such that, whenthey are each vertically oriented spatially, incident light rays whichstrike said body anywhere within an included angle of about 360 in ahorizontal plane extending through said body are adapted to beretro-reflected.

It is an object of this invention to provide a reflex reflector bodyhorizontally viewable anywhere within an angle of 360 using only fourflattened reflective faces.

It is another object to provide such a reflector body which uses bothwide angle and standard reflex reflective molded facets in each suchface.

A further object is to provide a 360 reflex reflector using only one ortwo reflective bodies and having only a few retro-reflective surfacestherein.

A still further object is to provide an optimized construction for a 360reflex reflector, horizontally measured.

Other and further aims, objects, purposes, advantages, utilities, andfeatures will be apparent to those skilled in the art from a reading ofthe present specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is an isometric view of one embodiment of a reflex reflector ofthe present invention;

FIG. 2 is a transverse sectional view taken along the line IIII of FIG.1;

FIG. 3 is a plan view of the embodiment of FIG. 1 illustrating how 360reflex reflection is achieved there with;

FIG. 4 is an isometric view of another embodiment of a reflex reflectorof this invention;

FIG. 5 is a plan view of the embodiment of FIG. 4;

FIG. 6 is an isometric view of another embodiment of a reflex reflectorof this invention;

FIG. 7 is an isometric view of another embodiment of a reflex reflectorof the present invention;

FIG. 8 is an isometric view of another embodiment of a reflex reflectorof the present invention;

FIG. 9 is an isometric view of another embodiment of a reflex reflectorof the present invention;

FIG. 10 is an isometric view of another embodiment of a reflex reflectorof the present invention;

FIG. 11 is an enlarged isometric view of one embodiment of a pin;

FIG. 12 is a top plan view of the hexagonal pattern produced by aplurality of pins in a retro-reflective reflector;

FIG. 13 is a side elevational view of one cube corner in aretro-reflective reflector body;

FIG. 14 is a plot of the characteristic retro-reflected light intensityproduced by a plurality of facets of the type shown in FIG. 13;

FIG. 15 is a series of plots illustrating the manner in which the fieldof reflected light changes as the pin centers are angled from a verticalposition to a position inclined to the vertical;

FIG. 16 shows illustrative plots for a reflector of the type having bothstandard reflector facets and wide angle reflector facets; and

FIG. 17 is a plot illustrating the relationship between angle ofreflected light and intensity of reflected light at such angle bothhorizontally and vertically for a combination of wide angle and standardreflectors in a single reflector body.

DETAILED DESCRIPTION Turning to the drawings there is seen in FIGS. 1and 2 one embodiment of a reflex reflector body of the present inventionherein designated in its entirety by the numeral 15. Body 15 is adaptedto retro-reflect incident light over an included angle of at least 360measured in one horizontally extending plane 16. The body 15 has fourretro'reflective generally planar surface portions designated,respectively, as 18, 19, 20 and 21. Two of these portions, portions 18and 21, are generally in opposed, parallel relationship one with theother, and the remaining portions, portions 19 and 20, are likewise ingenerally opposed, parallel relationship to each other. Portions 18 and21 extend normally in relation to portions 19 and 20. Preferably, and asshown, portions 18, 19, 20 and 21 have substantially identical surfacereflective characteristics and each preferably has a similar perimetricshape.

Each of the portions 18, 19, 20 and 21 has incorporated thereinto atleast three different groups of retroreflective, prismatic facets. Thefacets in each group are identical to one another. In one group, thefacets are adapted to retro-reflect incident light striking such groupat an angle ranging from about 0 up to about 1 30 measured normallythereto in one direction within one plane (such as a plane 16, 26 or 27in FIG. 1, for example). The other two such groups are adapted toretro-reflect incident light striking such at an angle ranging from anangle which is not greater than the maximum retro-reflectance angle ofsuch one group up to an angle which is at least about 45 measured from anormal thereto in such plane, one of such other groups beingretro-reflective on one side of such normal, the other of such groupsbeing retro-reflective on the other side of such normal.

Thus, in the embodiment 15, using portion 21 as representative each oftwo different types of facets are arranged into at least two groupsintegrally formed in each of the surface portions 18, 19, 20 and 21. Ineach of the portions 18, 19, 20 and 21, any convenient arrangement orpattern of such groups may be employed. Thus, portion 21 is divided intothree such groups of facets, one group being designated 23, a secondgroup being designated 24, and a third group being designated 25. Thegroup 23 facets are adapted to retroreflect incident light striking sameat angles ranging from about up to about i 30 (measured in plane 27).The group 24 facets are adapted to retro-reflect light striking same atangles ranging from an angle not greater than about 30 up to an anglewhich is about 45 to the left of perpendicular or normal line 28 inplane 27 with respect to incident light rays striking surface portion 23in plane 27. The group 25 facets are adapted to retro-reflect lightstriking same at angles ranging from an angle not greater than about 30up to an angle which is about 45 to the right of perpendicular 28 inplane 27. Such portions 19, 20 and 21 are similarly divided into groups.

In the embodiment 15, each of the surface portions 18, 19, 20 and 21 hasa generally square configuration, but any convenient perimetricconfiguration may be employed for purposes of this invention.

The interrelationship between such groups and such portions 18, 19, 20and 21 is such that, when such portions 18, 19, 20 and 21 are eachvertically oriented spatially, incident light rays horizontally strikingsuch within an included angle of about 360 extending horizontally areretro-reflected. In order to enhance retroreflectance viewabilitycharacteristics of a body 15, it is preferred to have the respectiveportions 16, 17, 18 and 19 be further adapted to retro-reflect incidentlight striking same at angles ranging from about 0 up to about i 20 (andmore preferably 1 30, and still more preferably 1 45) measured normallythereto above and below such one plane therethrough, such as plane 27through representative portion 21. Thus, when the body is oriented so asto have its portions 18, 19, and 21 vertically spatially oriented, thisdirection is vertical with respect to the other direction which ishorizontal. Such characteristics are achieved by selection of facetgroups and by arrangement thereof, as those skilled in the art willappreciate.

The body 15 is formed of two subassemblies and 31, of which subassembly31 is representative (see FIG. 2). Each subassembly is formed of twopieces of molded transparent plastic, such as an acrylic resin, apolycarbonate resin, or the like, one piece being desig nated 32,theother 33. Each piece 32 and 33 has an outer flattened face 35 and 36,respectively and an inner face 37 and 38, respectively. Each inner face37 and 38 has molded thereinto the retro-reflective facets hereinabovediscussed (not drawn to scale in faces 37 and 38 in FIG. 2). Around theperimeter of each inner face 37 and 38 is formed an inwardly turningshoulder 39 and 40, respectively, which continuously extends about sideand end edges of each piece 32 and 33. The outside edge of each shoulder39 and 40 is adapted to make mating opposed engagement with the otherthereof to form subassembly 31, the shoulders 39 and 40 beingconveniently sealingly bonded to each other by means of an adhesive (notshown), or the like. Each subassembly 30 and 31 is equipped with an ear41 molded one half into each piece forming same (such as pieces 32 and33 of subassembly 31). Ears 41 aid in mounting a body 15. Any convenientor conventional means for mounting may be employed for mounting a body15, as those skilled in the art will appreciate. Subassembly 30 isconveniently mounted to subassembly 31 by a pin 42 which extends onehalf into each of a channel formed in respective subassemblies 30 and 31as shown in FIG. 1. Any convenient means may be used to secure suchsubassemblies 30 and 31 together.

Body 15 (see FIG. 3) is adapted to have 360 retroreflectivecharacteristics because each surface portion 18, 19, 20 and 21 thereofis adapted to retro-reflect incident light rays striking same over i 45as indicated above in reference to portion 21 and groups 23, 24 and 25thereof. Thus, portion 18 retro-reflects through a 90 angle 44, portion19 retro-reflects through a 90 angle 45, portion 20 retro-reflectsthrough a 90 angle 46, and portion 21 retro-reflects through a 90 angle47, so 360 retro-reflection of body 15 is achieved. Preferably, eachportion 18, 19, 20 and 21 is adapted to retro-reflect through an anglegreater than 90 so that an overlap between adjacent retro-reflectedlight areas from each portion 18, 19,-20 and 21 can occur to some extentso as to avoid any possibility of low retro-reflected light levels inoverlap regions which might make the body 15 harder to discern by aviewer located at a comer area from body 15. Those skilled in the artwill appreciate that operability of the present invention does notdepend upon reflectivity from any one reflective surface in any givenhypothetical plane, such as 26, 21 or 16, or on either side of any givennormal in such plane. Body 15 is suitable for use on construction sites,airport mnways, vehicles, and the like.

In FIGS. 4 and 5 is illustrated an alternative embodiment of a reflectorof this invention which is designated in its entirety by the numeral 48.Here a pair of triangles 49 and 50 are integrally interconnectedtogether at their adjoining or common apexes 51. Each outside,vertically spaced edge 52 and 53 of respective triangles 49 and 50 isequipped with an ear 54 and 55 for mounting purposes. Conveniently, eachtriangle 49 and 50 may be formed similarly to subassembly 31 of body 15and then the two triangles 49 and 50 joined together at apexes 51 by anadhesive or the like (not shown). A pin (not shown) such as in body 15may be employed to secure the triangles 49 and 50 together analogous tobody 15. Faces 56, 57, 58 and 59 are each similar to each other. Eachflattened outside face 56 and 57 of triangle 49, and each such face 58and 59 of triangle 50 has three groups of facets therein. For example,face 56 has groups 60, 61 and 62, and face 58 has groups 63, 64 and 65molded thereinto. Groups 60 and 61 and groups 63 and 64 are eachanalogous in properties to groups 24 and 25 of portion 21 of body 15,groups 62 and 65 are each analogous in properties to group 23 of portion21 of body 15.

In FIG. 6 is shown another embodiment designated in its entirety by thenumeral 67. Body 67 is adapted for use as a sign post or directive arrowcombination. Construction of body 67 can be similar to that used forbody 15.

In FIG. 7 is shown another embodiment designated in its entirety by thenumeral 68. Body 68, like body 48,

is suitable for use on a bicycle or the like. Construction can besimilar to that used for body 15.

In FIG. 8 is shown an embodiment designated in its entirety by thenumeral 69 which is similar to body 68 except that here a rod 70 isextended through the members 71 and 72 to secure such together in theindicated normal desired relationship. Rod 70 at its bottom end isfitted, as by crimping, threading, or the like, with a yoke 73 adaptedfor mounting body 69 to a frame member (not shown), such as a bicyclebasket, handlebar, fender, axle shaft, or the like. The upper end of rod70 is threaded and fitted with washer 74 and nut 75 for clamping theentire body 69 together.

In FIG. 9 is shown an embodiment which is designated in its entirety bythe numeral 77. Each of the reflectorized subassemblies 78 and 79 ofbody 77 can be constructed analogously to subassembly 31 of body 15. Thesubassemblies are adapted to be mounted in ve1tically spacedrelationship to each other, as illustrated, by means of a core bar 80which extends internally through diagonal corner portions of respectivediamond shaped subassemblies 78 and 79, subassembly 78 being fitted witha socket internally (not shown) in its upper comer 81. In manufacture,it is convenient to seal the halves of each subassembly 78 and 79 aroundbar 80.

In FIG. is shown an embodiment which is designated in its entirety bythe numeral 83. Body 83 is similar to body 77 except that in body 83subassembly 84 is not only vertically spaced from subassembly 85 but isadditionally horizontally translated in relation thereto. (although thelower left hand corner of subassembly 84 is spatially positionedimmediately above the right hand comer of subassembly 85, as shown inFIG. 10). Body 83 is useful with an obstruction such as wall member 86that interfere with the normal reflective function of subassembly suchas 84. Body 77 has a similar utility.

The interrelationship between a group of facets in a retro-reflectivereflector which is adapted to retroreflect at an angle of i 30 in onedirection compared to a group of facets in such reflector adapted toretroreflect at a side angle of up to about LL 45 is illustrative byFIGS. 11 through 19. In th manufacture of retroreflective reflectors ofthe type used in the present invention a plurality of so-called pins 150may be employed. Each pin, as shown here, is hexagonally shaped. Thetransverse distance B between flat sides is variable, but is typicallyof the order of about 0.094 inches while distance A between opposingsides is similarly variable,

but is typically about 0.108 inches. Three intersecting facets 151, 152and 153 are formed at the forward end of each pin 150. Each facet 151,152 and 153 traverses two sides of the hexagonal pin and has an apexcoinciding with the axis 154 of each pin 150. Each facet has an anglerelative to the axis of about 35 The pins are arranged into a pattern,such as shown in FIG. 12, and an electroform mold, or the like, is madeusing such pin pattern, the electroform being concurrently made byelectroplating nickel orthe like onto and over a plurality of alignedpin 151 heads. In such process the high points are reversed in mirrorimage fashion in the product mold (over the former low points in thepins) and vice versa, all as those skilled in the art will appreciate.From the product mold, a reflector element is molded. A section of theresulting reflector is shown in FIG. 13. When a reflector body having aplurality of individual facets, such as those shown in FIG. 13, iscaused to retro-reflect incident light, a characteristic pattern ofreflected light results, in solid line form shown by an isocandle perfoot candle curve in polar coordinates. When the facets of FIG. 12 arerotated through 180, a similar characteristic pattern as shown by thedotted line in FIG. 14 is produced. However, when one tilts the axis 154of each of a plurality of pins 151 arranged in a pattern such as shownin FIG. 12 from the vertical position shown in FIGS. 11-13, throughincreasing angles of common inclination, there is produced a changingfamily of characteristic patterns of reflected light, such as shown inFIG. 15, each succeeding plot 156, 157, and 158 representing anisocandle per foot candle curve in polar coordinates, each curverepresenting a greater inclination angle for a group of pins, which areelectro formed into a mold, and then the mold used to make a reflectorbody. The plots of FIGS. 14 and 15 are not for any specific reflectors,but only are given herein to illustrate the principles involved, whichare known already to those skilled in the art.

.Whenone tilts the axes 154 of such a plurality of such pins 151 in theopposite direction, then is produced a changing family of characteristiccurves like those in FIG. 15, but reversed.

When one combines into a single reflector body both the type ofcomposite reflex reflectance shown inFIG. 14 with the type shown in FIG.15, and, in addition, uses two standard sections such as shown in FIG.12 but with each section oriented 180 with respect to the other, thereis produced in a single reflector body both such types of reflectreflectance, that shown in FIG. 14 sometimes being known as a standardreflector having a characteristic reflectance value generally given as'1 30, that shown in FIG. 15 sometimes being known as a wide anglereflector having a characteristic reflectance value which can range verywidely from about 10 to 88, though values between about 25 and areparticularly and preferably useful. Such a combination reflector bodydisplays a plot of retroreflectance angle versus reflected lightintensity as shown in FIG. 16, lines 159, 160, and 161. Line 160 isproduced by the so-called standard retro-reflector facets, line 159 isproduced by the so-called wide angle retro-reflective facets sensitiveto light on the right side of the ordinate 162, and line 161 is producedby the socalled wide angle retro-reflective facets sensitive to light onthe left side of the ordinate 162.

If, for example, the number of standard facets is increased, the amountof reflected light increases (see dotted line 163). If, for example,both the number of wide angle facets and their respective angles ofinclination are increased for both right and left hand members, thedotted lines 164 and 165 result. United States government federalstandards for a bicycle reflector comprising such a combination of leftand right wide angle reflector groups in combination with a centrallyviewable standard reflector are shown in the illustrative plot of FIG.17. By combining different pin groupings at different respective facetaxis angles one can produce an unlimited gradation of retro-reflectancechar acteristics in a given retro-reflector, so that any given reflectorcan be produced by one skilled in the art within the limitations ofpins, materials of construction, design standards, and the like, usingknown technology.

Other and further embodiments and variations of the present inventionwill become apparent to those skilled in the art from a reading'of thepresent specification taken together with the drawings and no unduelimitations are to be inferred or implied from the present disclosure.

I claim:

1. A reflex reflector body adapted to retro-reflect incident light overan included angle of at least about 360.measured in onevplane comprisingA. a body having four retro-reflective, generally planar surfaceportions arranged into two pairs of two portions each, said portions ofeach such pair of portions being generally in opposed, parallel rela- Ytionship to each other, one such pair of portions being normallydisposed relative to the other thereof, each said portion having atleast one region comprised of transparent, solid material and having aregion axis normal thereto,

'B. support means holding each such pair of portions in fixed,substantially non-overlapping adjacent relationship relative to theother thereof,

C. each one of said regions having formed therein at least two groups ofcube comer reflector elements,

all such elements each having a central optical axis, the respectivesuch optical axes of such elements in each such group being disposedsubstantially parallel to the respective such optical axes of the othersuch elements in each such group, eachone of said regions further beingretro-reflective of light directed thereon over an angle extending up toat least about 45 on a pair of opposed sides of said region axis thereofin a first plane extending through said region axis thereof,

D. the respective optical axes of such elements in one such group beinggenerally parallel to said region axis in each said region, I

E. the respectiveoptical axes of such elements in a second such groupbeing inclined at a predeter-.

axis in eachsaid region, and the respective optical axes of suchelements in a third such group being inclined at a predetermined anglein a different direction relative to said region axis in each' saidregion, g

F. the'interrelationship between said groups, and said portions, beingsuch that, when said portions are each vertically oriented spatially,incident light rays striking said body anywhere within an included angleof about 360 ina horizontal plane extending horizontally through saidbody are adapted to be retro-reflected. r

2. The reflex reflector of claim 1 wherein said groups in each of saidportions are also adapted to retro-reflect incident light strikingeither of such facets at an angle ranging from 0 up to about i 20measured normally to said horizontal plane, and each of said firstplanes generally coplanar with said horizontal plane.

3. The reflex reflector of claim 1 wherein each of said portions issimilar to the other portions and the portions of each pair areinterconnected together.

4. A reflex reflector body of claim 1 wherein said respective pairsadjoin at intersecting edge portions.

5. A reflex reflector body of claim 1 wherein said respective pairs arein spaced relationship to each other.

6. The reflex reflector body of claim 5 wherein said spacing isvertical. i

7. The reflex reflector body of claim 5 wherein said spacing is verticaland horizontal.

8. A reflex reflector body of claim 1 further including mounting means.v

9. A reflex reflector body of claim 5 further including mounting means.

10. A reflex reflector body of claim 1 wherein each of said pairs istriangularly shaped.

11. A reflex reflector body of claim 10 wherein each of said pairs'hasfour sides.

1. A reflex reflector body adapted to retro-reflect incident light overan included angle of at least about 360* measured in one planecomprising A. a body having four retro-reflective, generally planarsurface portions arranged into two pairs of two portions each, saidportions of each such pair of portions being generally in opposed,parallel relationship to each other, one such pair of portions beingnormally disposed relative to the other thereof, each said portionhaving at least one region comprised of transparent, solid material andhaving a region axis normal thereto, B. support means holding each suchpair of portions in fixed, substantially non-overlapping adjacentrelationship relative to the other thereof, C. each one of said regionshaving formed therein at least two groups of cube corner reflectorelements, all such elements each having a central optical axis, therespective such optical axes of such elements in each such group beingdisposed substantially parallel to the respective such optical axes ofthe other such elements in each such group, each one of said regionsfurther being retro-reflective of light directed thereon over an angleextending up to at least about 45* on a pair of opposed sides of saidregion axis thereof in a first plane extending through said region axisthereof, D. the respective optical axes of such elements in one suchgroup being generally parallel to said region axis in each said region,E. the respective optical axes of such elements in a second such groupbeing inclined at a predetermined angle in one direction relative tosaid region axis in each said region, and the respective optical axes ofsuch elements in a third such group being inclined at a predeterminedangle in a different direction relative to said region axis in each saidregion, F. the interrelationship between said groups, and said portions,being such that, when said portions are each vertically orientedspatially, incident light rays striking said body anywhere within anincluded angle of about 360* in a horizontal plane extendinghorizontally through said body are adapted to be retro-reflected.
 2. Thereflex reflector of claim 1 wherein said groups in each of said portionsare also adapted to retro-reflect incident light striking either of suchfacets at an angle ranging from 0* up to about + or - 20* measurednormally to said horizontal plane, and each of said first planesgenerally coplanar with said horizontal plane.
 3. The reflex reflectorof claim 1 wherein each of said portions is similar to the otherportions and the portions of each pair are interconnected together.
 4. Areflex reflector body of claim 1 wherein said respective pairs adjoin atintersecting edge portions.
 5. A reflex reflector body of claim 1wherein said respective pairs are in spaced relationship to each other.6. The reflex reflector body of claim 5 wherein said spacing isvertical.
 7. The reflex reflector body of claim 5 wherein said spacingis vertical and horizontal.
 8. A reflex reflector body of claim 1further including mounting means.
 9. A reflex reflector body of claim 5further including mounting means.
 10. A reflex reflector body of claim 1wherein each of said pairs is triangularly shaped.
 11. A reflexreflector body of claim 10 wherein each of said pairs has four sides.